The invention relates to a water-conducting domestic appliance.
To prevent damage during operation of water-conducting domestic appliances, especially dishwashers and washing machines, caused by the unwanted escape of water, it is known from the prior art that the water supply can be interrupted by closing water inlet valves if the device starts to leak.
To prevent water from escaping from the domestic appliance if the water inlet valves do not close completely and to improve the water safety of switched-off domestic appliances, especially of dishwashers and washing machines, a water safety device is known from DE 35 44 307 A1 in which, if a fault causes water to escape while the device is switched off, a drain pump is automatically activated.
The safety device in this case comprises a main switch, a water cutoff switch and also a controller for activating a drain pump. The main switch and the water cutoff switch are each assigned a connection to the electrical mains, with the water cutoff switch able to be switched by a float.
When the main switch is closed, the drain pump is controlled during normal operation of the domestic appliance by control electronics.
In the event of a leak the water cutoff switch overrides the main switch of the domestic appliance and connects the drain pump directly to the electrical mains. The drain pump is thus activated independently of the position of the main switch directly by the water cutoff switch. After an activation of the drain pump by the water cutoff switch the problem arises of a defect in the water cutoff switch meaning that the drain pump is in operation without interruption and runs the risk of overheating.
A safety circuit for water-conducting domestic appliances, especially washing machines and dishwashers, is known from DE 198 09 114 C1, which features an additional logic circuit supplied permanently from the mains voltage, one of the functions of which is to connect a process controller to the power supply on the detection of a leakage, with the process controller then initiating predetermined switching processes via components such as pumps for example of the domestic appliance as a function of the activation conditions obtaining However standby power losses occur as a result of the permanent supply of mains voltage to the logic circuit.